Remote motor control



p 1944- J. A. VAN LAMMEREN EIAL 2,345,773

REMOTE MOTOR CONTRQL Filed Marbh 15, 1941 I 2 Sheets-Sheet 2 INVENTORS JO/M/W/ESA. VAN LAMMEREN 7.25 m ER ME) A'T'roRNEY Patented Apr. 4; 1944 REMOTE MOTOR CONTROL Johannes Antonius van Lammeren and W'y tze Hendrik van dcr Mey, Eindhoven, Netherlands; vested in the Alien Property Custodian Application March 15, 1941, Serial No. 383,524 In the Netherlands September 13, 1939 8 Claims.

This invention relates to a radio-receiver comprising a motor having an axially movable shaft for performing more than one control function.

Radio receivers which can be tuned by means of push buttons may be devised in such manner that after depression of a push button the tuning means are brought into the position corresponding to the desired station by means of a motor. The use of a motor for operating the tuning means is particularly advisable when the receiver is to be tuned at a distance.

In the last-mentioned case it is advisable that additional control functions such as, for instance, the choice of the wave range, volume control, adlustment of the band-width and so on should be performed by means of a motor. For the additional functions it has already been proposed, as in the Manson et a1. Patent No. 1,926,393, to incorporate one or more separate motors in the receiver. However, this is an expensive solution which, moreover, requires much space in the receiver.

Again it is mown to use one motor for more than one control function. The receiver, for instance, may be devised so that the motor operates the tuning means in one direction of rotation and the Wave-range switch in the other direction of rotation as disclosed and claimed in our Patent No. 2,312,035, issued on February 23, 1943.

It has already been suggested to utilize the axial displacement of the motor-shaft for increasing the number of control functions to be fulfilled. When the motor is normally energized the shaft is shifted until the armature extends in the field. Thus a mechanical coupling with the tuning means is established. If, on the other hand the.

motor is energized by a weaker current the shaft is not shifted or to an insuflicient degree so that the motor may actuate a potentiometer for volume control. However, this has the drawback that the motor can develop only a small torque and it is not very sure that the shaft will not shift or only to a slight extent.

To avoid these drawbacks displacement of the shaft during the performance of one control funetion is rendered impossible prior to putting the motor into circuit for the performance of another control function.

The invention will be more clearly understood by reference to the accompanying drawings, wherein Fig. 1 shows in diagrammatic fashion one form of oomtruction whichembodies the present invention, Fi 2 shows the electrical circuit utilized in the system or we. 1, and Fig. 3 i a modified form of circuit which may be used in electric motor whose armature 2 is mounted on a shaft 3 which 'is movabl in an axial direction, indicated by the double arrow a. .The shaft 3 has mounted on it two pinions 4 and 5. In the position of shaft 3 illustrated in the drawings the pinion i meshes with a toothed wheel 8 secured on the shaft of a potentiometer l. potentiometer '5 serves to control the sound strength or volume of the radio receiver. When the shaft 3 is shifted to the right the engagement is interrupted and pinion 5 meshes with a toothed wheel 8 secured on the shaft of the diagrammatically represented tuning means 9. When the motor is not energized the shaft is kept in the represented position by a leaf spring I0 which together with leaf spring H constitutes a contact which is closed when the shaft 3 is shifted to the right. In the illustrated position the armature 2 partly extends beyond the hold of the stator. Upon energization the armature is completely drawn into the field of the stator so that the coupling between toothed wheels t and 5 is interrupted and a coupling is established between toothed wheels 5 and 8. At the same time the spring contact iii-H is closed. This contact is, for instance, connected in parallel with the loudspeaker LS of the receiver so that the loudspeaker is short-circuited during control of the tuning means.

If, however, displacement of the motor shaft 3 is prevented during energization of the motor, the letter on being put into circuit drives the potentiometer l for volume control instead of the tuning means 9.

For blocking the motor shaft there is provided a relay i 2 having an exciting coil l2 and a pivoted armature 13 to one end of which is se-= cured a plunger bar it which is movable along a straight guide it. Normally the armature it assumes the raised position shown in the drawlngs by action of the spring l8. Upon energization of the relay it the bar it is moved downwardly in the path of the motor shaft so that the latter is prevented irom moving to the right. Consequently the relay is must be energized before putting the motor 5 into circuit. To this end the relay 52 operates several spring contacts 2 3,, 25 by which energiaation of the motor is initiated. This will now be explained in connection with the circuit of Fig. 2.

The motor l which is of the reversible type and is provided with the field windings R and L The is fed from power mains connected between the terminals ii and 98. Associated with the motor field windings are two spring biased armatures i9 and Ell controlled lay relays 2i and 22 respec tively. In the position shown in the drawings'the two relays 2i and 22 are not energized and the motor circuit is interrupted. When solely the relay it is energizcdits armature i9 is closed and the motor operates, for instance, in a left-hand direction, since only the motor field winding L is energized. When, on the contrary, both'relays 2i and 22 are energized the armatures is and 2d are operated, and as a result of which the motor operates, for instance, in a right-hand direction, since then only the motor field winding R is energized. Energization of the relays 2i and 22 is effected through the intermediary of a transformer 23 which is also fed from the Power mains connected between terminals H and is. This transformer serves at the same time to energize through a manually controlled contact de closed by means of another push-button bearing the inscription softer."

Closure of only contact 2? resultsin the relay l2 being energized by transformer 23. Du to this, the bar it is forced down into the path of the motor-shaft as a result of which the shaft is prevented from movingto the right. However, one to the fact that the armature 2 e2 tends partly in the field of the stator the motor eserve shaft cannot surmount this force and is conse-.

Qllelltll? prevented from being displaced.

For the automatic control of the receiver tuning means any suitable known arrangement may be utilized, as for example, that shown in Patout No. 2,204,065, issued on June 11, 1940, to Beizer et al. As diagrammatically shown in Fig. 2, the arrangement comprises, a two-part reversins commutator 35, a plurality of adjustable station selecting contacts to, and a plurality of manually operated contact keys ill. Since such motor-operative automatic tuner and its mode of operation are well known in the art, further description thereof is believed unnecessary.

What we claim is:

l. in radio apparatus, the combination with tuning and volume control devices therefor, oi a motor having a shaitror actuating said devices, said shaft being axially movable and having two positions of operation, one for actuating one of:

said devices and a second position for actuatingv V the other of said devices, a first means upon actuation thereof .for energizing the circuit of the motor, electro-mechanical means operative upon said energization of the motor circuit to restrain the motor shaft in one of its two positions whereby the motor actuates the one said device, and a second independent means upon actuation thereof for energizing the motor and for slmul:

taneously shifting the shaft to its second posiremains coupled through gears i and ii to the potentiometer for- Volume control. At the same time due to the energization of 12 spring contacts 2t and 25 are closed. Only the relay it will now be energized through spring contact 2 3 and contact 2'8 (contact zfi being open) so that the motor resumes its action in a left-hand direction and the sound strength is increased. Closure of contact}? and in addition contact 28 causes also the relay 22 to be energized through spring contact 25 and contact 28 and as a result of which the motor resumes its action in a righthand direction thus reducing the sound strength.

Figure 3 represents another embodiment of the invention.

The circuit shown in Figure 3 substantially corresponds to that shown in Figure 2. For sim plicity the motor 5 and its connections appearing to the right of the line r-c: in Figure 2 is omitted from Figure 3.

In Figure 3 the relay exciting coil l2 shown in Figure 2 is replaced by two series-connected relay exciting coils 29 and 3B. Coil 28 exclusive- 1y operates both spring contacts 25 and 25, where as the coil se of the relay 3% exclusively serves to prevent displacement of the motor shaft 3.

For this purpose the relay 3c is equipped withan armature 3i loosely engaging the core 32 so that the magnetic circuit of the relay Elli is closed till tion whereby the motor actuates the said other device.

2. in radio apparatus, the combination with tuning and volume control devices therefor, of a motor having a shaft for actuating said devices, said shaft being axially movable and having two positions of operation, one for actuating one of said devices and a second position for actuatin the other of said devices, a first means upon ac= tuation thereof for energizing the circuit of the motor, a relay included in the motor circuit and operative upon energization of said circuit to hold the motor shaft at one of its two positions where loy the motor actuates the one said device, and a second independent means upon actuation thereof for energizing the motor exclusive of the relay and for simultaneously shifting the shaft to its second position whereby the motor actuates the said other device.

3. In radio apparatus, the combination with tuning and volum control devices therefor, of a reversible motor having a shaft for selectively actuating said devices, said shaft being axially shiitable to two positions of operation, one for actuating one of said devices and a second position for actuating the other of said devices, a-

pair of. relay-operated switches for determining the direction of rotation oi the motor, a control circuit including a relay provided with a pair of normally open switches and a stop member, manual means for energizing the control circuit to so operate the direction determining relays to control the direction or motor rotation and to hold by means of the stop member the motor shaft at one of its two positions whereby the motor actuates the one said device, and a second means exclusive oi? the pair or relay-operated switches for encrginng the motor and for simultaneously shifting the shaft to its second position whereby the motor actuates the said other device.

4. In radio apparatus of the type provided with a tuning device and a volume control device, control mechanism therefor comprising a single reversible motor and a shaft actuated thereby, said shaft having a normal position and being axially shiftable to a second position of operation, said shaft in the normal position controlling one of said devices and in the second position controlling the other of said devices, first means under control of manually operated keys at a remote point for energizing the circuit of the motor, means operative upon said energization of the motor circuit to hold the motor shaft at its normal position whereby the motor actuates, the one said device, and second means independent of the motor shaft holding means for energizing the motor and for simultaneously shifting the shaft to its second position whereby the motor actuates the said other device.

5. In radio apparatus, the combination with a pair of devices to be adjusted, of a motor having a shaft for actuating said devices, said shaft being axially movable and having two positions of operation, one for actuating one of said devices and a second position for actuating the other of said devices, means for energizing the circuit of the motor, and electro-mechanical means operative upon said energization of the motor circuitto restrain the motor shaft in one of its two positions whereby the motor actuates the one said device.

6. In radio apparatus, the combination with a pair of control devices therefor to be adjusted,

of a motor having a shaft for actuating said devices, said shaft being axially movable and havin two positions of operation, one for actuating one of said devices and a second position for ac tuating the other of said devices, means for enereizins the circuit of the motor, a stop member,

and a relay for actuating the stop member included in the motor circuit and operative upon energization of said circuit to cause the stop member to hold the motor shaft at one of its two positions whereby the motor actuates the one said device.

'7. In radio apparatus, the combination with a pair of control devices therefor to be adjusted. of a reversible motor-having a shaft for selectively actuating said devices, said shaft being axially shiftable to two positions of operation, one for actuating one of said devices and a second position for actuating the other of said devices. a pair of relay-operated switches for determining the direction of rotation of the motor, a control circuit including a relay provided with a pair of normally open switches and a stop member, and manual means for energizing the control circuit to so operate the direction determining relays to control the direction of motor rotation and to hold by means of the stop member the motor shaft at one of its two positions whereby the motor actuates the one said device.

8. In radio apparatus of the type provided with a tuning device and a volume control device, control mechanism therefor comprising a single reversible motor and a shaft actuated thereby, said shaft having a normal position and being axially shiftable to a second position of operation, said shaft in the normal position controlling one of said devices and in the second position controlling the other of said devices, means under control of manually operated keys at a remote point for energizing the circuit of the motor, and means operative upon said energization of the motor circuit to hold the motor shaft at its normal position whereby the motor actuates the one said device.

J OHANNES ANTONIUS VAN LAMMEREN.

wit'rzE HENDRIK vnw m MEY. 

